The invention relates to gripping filaments.
Oral brushes, e.g., toothbrushes, often include a handle, a head and tufts of bristles extending from the head.
The bristles of the oral brush are often made from filaments. In some oral brush manufacturing processes filaments are provided in the form of a hank that is circular in cross section, has a height ranging from a few centimeters to several meters, and includes a band around its circumference. The band holds the filaments together.
Prior to incorporation into the oral brush, the hanks, and thus the filaments, are cut to a length of a few centimeters. The band is then removed and the filaments can be transferred to a magazine for further processing. Once the band is removed these short filaments become very difficult to handle.
In one aspect, the invention features a gripper that includes a) a first element that includes a plurality of male components, and b) a second element that includes a plurality of female components dimensioned to receive the male components. The first element and the second element are moveable from an open position to a closed position; the male components engage the female components when the elements are in a closed position. The individual male components and the individual female components are capable of maintaining a plurality of bristles in fixed relation to each other when the elements are in a closed position. In one embodiment, the female component or the male component is spring loaded. In another embodiment, the gripper further includes a spring extending from one of the first element or the second element to one of the female component or the male component. In one embodiment, the spring exerts a force against the female component in the direction of the male component. In other embodiments, the gripper further includes a means for biasing one of the female component or the male component against the other of the female component or the male component.
In some embodiments, the female components are removable from the second element. In other embodiments, the male components are removable from the first element. In some embodiments, the male components are removable from the first element, and the female components are removable from the second element.
In other embodiments, the gripper further includes a transport connected to the gripper. In one embodiment, the transport is capable of moving the gripper from a first position to a second position. In some embodiments, the transport is capable of rotating the gripper. In another embodiment, the female components include an entrance defmed by a first side wall, a second side wall, and a seat disposed between the first side wall and the second side wall. In one embodiment, the first side wall includes a tapered surface. In other embodiments, the second side wall includes a tapered surface.
In another embodiment, the male components include a finger. In one embodiment, the male components include a finger, a first guide member extending from the finger, and a second guide member extending from the finger.
In some embodiments, the gripper is automated. In other embodiments, the male components and the female components are capable of maintaining a plurality of tufts of bristles having two unfused ends in fixed relation to each other. In another embodiment, the male components and the female components are capable of maintaining a plurality of tufts of bristles in fixed relation to each other where the tufts have a fused end.
In another aspect, the invention features a method of transferring a plurality of tufts of bristles using an above-described automated gripper. The method includes 1) closing the elements of the gripper such that a plurality of tufts of bristles are maintained in fixed relation to each other between the male components and the female components of the gripper, and 2) moving the gripper. In one embodiment, the method further includes releasing the tufts of bristles. In some embodiments, the step of releasing includes placing individual tufts of bristles in openings in an article, e.g., a carrier bar or a mold insert. In other embodiments, the step of moving the gripper includes moving the gripper from a first position to a second position.
In other aspects, the invention features a gripper holding bristles that includes a first element, a second element, and a plurality of tufts of bristles having two unfused ends. The gripper maintains the tufts in fixed relation to each other between the first element and the second element. In one embodiment, the first element includes a male component. In other embodiments, the second element includes a female component.
In another aspect, the invention features a method for transporting tufts of bristles having two unfused ends, the method includes gripping a plurality of tufts of bristles having two unfused ends such that the tufts are maintained in a fixed relation to each other, and moving the plurality of tufts.
In other aspects, the invention features a bristle processing system that includes 1) a station that includes a plurality of tufts of bristles, and 2) an automated gripper for gripping the tufts, where the gripper includes a) a first element that includes a plurality of male components, and b) a second element that includes a plurality of female components dimensioned to receive the male components, the first element and the second element being moveable from an open position to a closed position, wherein the male components engage the female components when the elements are in a closed position. The individual male components and the individual female components are capable of maintaining the tufts of bristles in fixed relation to each other when the elements are in a closed position.
In one embodiment, the bristle processing system further includes a fusing apparatus that includes a heat source, where the fusing apparatus is capable of fusing the ends of the bristles to form fused tufts of bristles.
In another aspect, the invention features a method of processing a plurality of tufts of unfused bristles. The method includes 1) gripping a plurality of tufts of bristles having two unfused ends between a first element and a second element of an automated gripper, 2) transporting the tufts of unfused bristles in fixed relation to each other, and 3) releasing the tufts of unfused bristles. In one embodiment, the method further includes fusing one of the ends of the tufts of bristles.
The grippers can be used to grip and transport a number of tufts of bristles simultaneously. The grippers can also simultaneously shape a number of tufts.
The male and female components that constitute the gripper elements can be removable from the gripper. If a male component or a female component becomes damaged and needs replacing, the entire gripper remains useful because the individual component can be removed and replaced with a functioning component. In addition, the gripper can include any number of gripper elements (i.e., male and female component pairs), which enables the gripper to be constructed to simultaneously grip a desired number of tufts of bristles. The gripper can be modified as needed to include any number of gripper elements and any type of gripper element (e.g., gripper elements defining various tuft shapes and more than one tuft shape on a single gripper).
One of the male component or the female component can also be spring loaded such that it is biased toward the other component. The bias allows the gripper to comply with the variances that are inherent in simultaneously gripping multiple tufts that include multiple bristles. Such variances include, e.g., variances that influence the cross-sectional dimension of the tuft including, e.g., a variance in the number of bristles in the tuft or a variance in the diameters of the bristles within the tuft.
The grippers are useful for transferring tufts of bristles from and to stations were the bristles undergo processes including, e.g., end rounding, fusing, cutting, and tufting.
Other features and advantages of the invention will be apparent from the following description of the preferred embodiments thereof, and from the claims.